我国特有珍稀花卉植物蝟实生殖生物学特性研究

Studies on Reproductive Biology Characteristics of Kolkwitzia amabilis,an Endemic to China

通过用石蜡切片、扫描电子显微镜以及数量统计与分析的方法,研究蝟实大孢子发生及其雌配子体发育的特征;种子发育特点以及种子在果实中发育的数量变化。结果表明:其胚珠倒生,薄珠心,单珠被,大孢子四分体呈直线排列,功能大孢子位于合点端。胚囊发育类型属于蓼型。蝟实的胚胎学特征与忍冬科的胚胎学特征基本相同;在植株上种子胚的发育停留在鱼雷型胚时期,这属于种子的后熟现象。得出的结论是:蝟实胚发育停留在鱼雷型胚时期,种子发育不完全及败育率非常高(61.86%)是影响蝟实繁育的主要内因,也是蝟实稀有及孤岛状分布的原因。

Kolkwitzia amabilis, an endemic species to China, we studied reproductive biology characteristics of it through paraffin sectioning and scanning electron microscopy. That contains ： the characteristics of its megasporogenesis and development of the female gametophyte; the characteristics of development of the seed and the quantity movement of the seed among its development. The results showed that the ovule was anatropous, unitegmic and tenuinucellate type; the megaspore develop into a linear tetradas. The chalazas megaspore were a functional one, which develops into a polygonum type of embryo sac. The embryological characteristics of K. anmabilis were very similar to those of Caprifoliaceae. The embryo was depauperatus and remains at torpedo-stage embryo in the seed of it, possibly, which was afterripening phe- nomenon of the seed. The rate of abortive seed was 61.86%, and it perhaps major unit causation that affect breeding po- tential of Kolkwitzia amabilis. And it may be the major causation of that it＇s rare and isolated island shape distribution.